2013

6.3

1985

8.3

1997

7.9

1994

8.7

1990

7.4

2010

8.4

2008

8.5

2001

7.4

2014

6.5

2011

7.3

1972

8.7

1995

8.0

1979

8.2

1992

6.8

2012

6.7

2006

7.5

1987

7.3

2013

6.5

2012

7.4

2009

7.6